Bill Maher and his sexy neuroscientist girlfriend, Cara Santa Maria, have split, but not before the liberal talking head created an HBO pilot for his 26-year-old former gal pal, who moonlights as a model. The TV host and the science expert ended their two-year relationship in the spring after Maher convinced HBO to produce a pilot for a late-night show centered around his lady titled “Talk Nerdy to Me.” Maher appeared in the introduction and planned to be an executive producer if the pilot was picked up. Some insiders worried that the 55-year-old perennial bachelor would struggle running the show while still in the relationship. Maher’s dating roster has ranged from sharp-tongued conservative Ann Coulter to hip-hop model Karrine Steffans. Maher once said, “I’m just into women who are real, and they happen to be black.” An HBO rep said: “HBO declined to move forward on the pilot several months before Bill and Cara mutually decided to end their relationship.”